#include<iostream>
#include<cstdio>
#include<unistd.h>
#include<cstring>

int main()
{
    //库函数
    printf("hello printf\n");
    fprintf(stdout, "hello fprintf\n");
    const char *s = "hello fwrite\n";
    fwrite(s, strlen(s), 1, stdout);

    //系统调用
    const char *ss = "hello write\n";
    write(1, ss, strlen(ss));

    //???
    fork();
    

    //向标准输出进行打印 ， stdout cin -> 1 
    //std::cout << "hello cout" << std::endl;
    //printf("hello printf\n");
    
    //向标准错误进行打印，stderr，cerr -> 2, 显示器
    //std::cerr << "hello cerr" << std::endl;
    //fprintf(stderr, "hello stderr\n");

    return 0;
}
